Prediction of Aerobic Plate Count on Beef Surface Using Fluorescence Fingerprint

The potential of fluorescence fingerprint (FF) spectroscopy was investigated to develop a nondestructive prediction method of aerobic plate count on a beef surface. Sixty samples (e.g., 30 lean meat slices each of Australian cattle and Japanese cattle) stored aerobically at 15 °C were analyzed by front-face fluorescence spectrophotometry. FF and aerobic plate count (APC) were measured after 0, 12, 24, 36, and 48 h of storage. FFs were collected in both excitation and emission wavelength ranges of 200–900 nm. Partial least-squares regression (PLSR) performed on an FF dataset predicted an APC in the bacterial contamination load range from 1.7 to 7.8 log?colony-forming units (cfu)/cm² with a prediction error of 0.752 log cfu/cm². The regions where the regression coefficient of the PLSR model was relatively high were consistent with those of the FF peaks of five intrinsic fluorophores: tryptophan, NAD(P)H, vitamin A, porphyrins, and flavins. This suggests that changes in the autofluorescence of these intrinsic fluorophores due to the metabolism of bacterial flora on meat are reflected in the PLSR model for predicting APC from the FF dataset. FF spectroscopy coupled with multivariate analysis appeared to be applicable to the nondestructive determination of APC on the surface of lean beef.     

Rhodium-incorporated faujasite prepared at 80 °C

Rhodium-incorporated zeolites were synthesized from orthosilicate, aluminum nitrate, and rhodium chloride at 80 °C. Crystal phase diagram (zeolite types as functions of rhodium feed ratio and reaction period) showed that pure faujasite was formed in a wide range, but prolonged reaction caused partial transformation from faujasite to cancrinite at the rhodium feed ratio Rh/(Al + Rh) ≤ 0.02 and to gismondine at Rh/(Al + Rh) ≥ 0.4. X-ray diffraction analysis illustrated that an increase in the rhodium feed ratio caused appreciable decreases in the d-spacings, suggesting that rhodium was incorporated into the faujasite framework. ICP-OES analysis for the products showed that the rhodium content increased almost linearly with the increase in the rhodium feed ratio with an upper limit of the analyzed Rh content Rh/(Al + Rh) = 0.183 at the Rh feed ratio of 0.3. The products were almost quantitatively ion-exchanged using an ammonium chloride aqueous solution to study the ammonia desorption profiles on TG-DTA/MS analysis in the heating process. Considerably sharp exothermic peaks were observed at 245 °C simultaneously in the heating process. These peaks are probably related to catalytic decomposition of ammonia and desorption of ammonia, nitrogen, and water in the zeolite. A hypothesis was proposed for this mechanism: rhodium can be abruptly eliminated at an elevated temperature from the zeolite framework toward the micropores to form its hydroxides or oxides, then they triggered a catalytic decomposition of the adsorbed ammonia. The effect of calcination on crystallinity of the products and catalytic reactivity for hydrogen peroxide decomposition supported the proposed mechanism.     

Development of a Dense Electrolyte Thin Film by the Ink-Jet Printing Technique for a Porous LSM Substrate

Recently, the fabrication and development of novel solid oxide fuel cell (SOFC) structures were conducted with the aim of enhancing power generation. Newly cathode-supported honeycomb-type SOFC with a promising power/volume ratio is under development. However, the conventional processing techniques used for the fabrication of different SOFC cell components (electrolyte and electrode) are not compatible with the newly constructed honeycomb structure. The ink-jet printing technique may offer the ability to design and fabricate SOFC components on honeycomb substrates and complex 3D structures. In this study, the formation of a dense Gadolinium-doped ceria thin film on a cathode-supported LaSrMnO₃ substrate by the ink-jet printing technique was investigated.     

Anomalous plutonium isotopic ratios in sediments of Lake Qinghai from the Qinghai-Tibetan Plateau, China

The vertical profiles of (239+240)Pu and (137)Cs activities and (240)Pu/(239)Pu isotopic ratios are determined for three sediment cores of Lake Qinghai from the Qinghai-Tibetan Plateau, China, and compared with those in sediments of another three lakes (Lakes Bosten, Sugan, and Shuangta), the only existing ones closest to Lop Nor area, China's nuclear weapons test site in the northwestern part of the country. The mean inventory of 47.7 ± 18.7 MBq km(-2) for (239+240)Pu activity in Lake Qinghai is comparable to the average value of global fallout expected at the same latitude, yet the mean inventory of 1112.0 ± 78.0 MBq km(-2) for (137)Cs is slightly lower than that of global fallout. Anomalously low (240)Pu/(239)Pu isotopic ratios (0.038-0.125) were found in the 3-6.5 cm deep sediment layers, indicating the trace Pu input from early nuclear weapons research activities at Atomic City in the lake's watershed during the 1950-60s. Model calculation indicated that the Pu input accounted for approximately 5-16% of the total Pu inventory. The observation of low (240)Pu/(239)Pu ratio in the deep sediment layer provided a new time marker for recent sediment dating in the lake and around the area. The results are of great significance to the further understanding of sources, records, and environmental impacts of global and regional nuclear activities in the environment and provide important chronological information for further studies on the water eutrophication process and climatic change, and reconstruction of pollution history of organic contaminants and heavy metals in the watershed of Lake Qinghai.     

Visualization of Gluten,Starch, and Butter in Pie Pastry by Fluorescence Fingerprint Imaging

Food and Bioprocess Technology - The distribution of starches, proteins, and fat in baked foods determine their texture and palatability, and there is a great demand for techniques to visualize the...     

Inter-laboratory evaluation studies for establishment of notified ELISA methods for allergic substances (peanuts)

Inter-laboratory evaluation studies were conducted for ELISA methods for allergic substances (peanuts). Extracts of biscuit, sauce, chocolate and butter spiked with peanut standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate in 10 laboratories. Coefficients of variation (CVs) of the ELISA methods using a Peanut Protein ELISA Kit (Peanut kit) and a FASTKIT Peanut ELISA kit (Peanut ELISA kit) were mostly below 10%. Mean recoveries of the peanut standard protein from the food extracts were over 40% in the two ELISA methods. Repeatability relative standard deviations of peanut standard protein in four food extracts were in the ranges of 15.2-49.7% and 3.0-28.3% for the Peanut kit and the Peanut ELISA kit, respectively. Reproducibility relative standard deviations of peanut standard protein in four food extracts were 23.5-44.4%, 9.6-28.4% for the Peanut kit and the Peanut ELISA kit, respectively. The detection limits of both ELISA methods were 2-2.5 ng/mL in sample solutions. These results suggested that the notified ELISA methods are reliable and reproducible for the inspection of peanut protein levels in extracts of biscuit, sauce, chocolate and butter.     

137Cs in the western South Pacific Ocean

The 137Cs activities were determined for seawater samples from the East Caroline, Coral Sea, New Hebrides, South Fiji and Tasman Sea (two stations) Basins of the western South Pacific Ocean by gamma spectrometry using a low background Ge detector. The 137Cs activities ranged from 1.4 to 2.3 Bq m(-3) over the depth interval 0-250 m and decreased exponentially from the subsurface to 1000 m depth. The distribution profiles of 137Cs activity at these six western South Pacific Ocean stations did not differ from each other significantly. There was a remarkable difference for the vertical profiles of 137Cs activity between the East Caroline Basin station in this study and the GEOSECS (Geochemical Ocean Sections Study) station at the same latitude in the Equatorial Pacific Ocean; the 137Cs inventory over the depth interval 100-1000 m increased from 400+/-30 Bq m(-2) to 560+/-30 Bq m(-2) during the period from 1973 to 1992. The total 137Cs inventories in the western South Pacific Ocean ranged from 850+/-70 Bq m(-2) in the Coral Sea Basin to 1270+/-90 Bq m(-2) in the South Fiji Basin. Higher 137Cs inventories were observed at middle latitude stations in the subtropical gyre than at low latitude stations. The 137Cs inventories were 1.9-4.5 times (2.9+/-0.7 on average) and 1.7-4.3 times (3.1+/-0.7 on average) higher than that of the expected deposition density of atmospheric global fallout at the same latitude and that of the estimated 137Cs deposition density in 10 degrees latitude by 10 degrees longitude grid data obtained by Aoyama et al. [Aoyama M, Hirose K, Igarashi Y. Re-construction and updating our understanding on the global weapons tests 137Cs fallout. J Environ Monit 2006;8:431-438], respectively. The possible processes for higher 137Cs inventories in the western South Pacific Ocean than that of the expected deposition density of atmospheric global fallout may be attributable to the inter-hemisphere dispersion of the atmospheric nuclear weapons testing 137Cs from the northern stratosphere to the southern one and its subsequent deposition, and water-bearing transport of 137Cs from the North Pacific Ocean to the western South Pacific.     

Hydrophilic and photocatalytic properties of the SiO2/TiO2 double layers

The hydrophilic and photocatalytic properties of the SiO₂/TiO₂ double layers composed of a 20-nm-thick porous SiO₂ layer on the 200-nm-thick columnar anatase TiO₂ layer were studied. The hydrophilicity of the double layers was strictly determined by the relative coverage of organic contaminants. The intrinsic hydrophilicity of 0° of SiO₂ in terms of the water contact angle was restored by the photocatalytic decomposition of organic contaminants under the UV light irradiation.Electron spin resonance measurements revealed the generation of OH radicals under the UV light irradiation onto the SiO₂/TiO₂ double layers. Photoconductivity measurements showed that the current decay in O₂ gas atmosphere was remarkably fast in comparison with that in H₂O vapor. These observations support our view that the generation of OH radicals effective for decomposing organic contaminants on the surface begins with the reaction between O₂ molecules and the photoexcited electrons. We propose together with other experimental facts herein that OH radicals would be generated via O₂⁻ and H₂O₂ in the double layer system.     

Robust and adaptive keypoint-based object tracking

Object tracking is a fundamental ability for a robot; manipulation as well as activity recognition relies on the robot being able to follow objects in the scene. This paper presents a tracker that adapts to changes in object appearance and is able to re-discover an object that was lost. At its core is a keypoint-based method that exploits the rigidity assumption: pairs of keypoints maintain the same relations over similarity transforms. Using a structured approach to learning, it is able to incorporate new appearances in its model for increased robustness. We show through quantitative and qualitative experiments the benefits of the proposed approach compared to the state of the art, even for objects that do not strictly follow the rigidity assumption.     

A translucent display algorithm for G-octree represented grey-scale images

A new translucent display algorithm is proposed for grey-scale images represented by G-octrees. The algorithm generates a special triangle quadtree as the display image for the isometric projection of a G-octree, while traversing the G-octree from front to back, with respect to the viewpoint. A method of using the translucent effect to analyse the interiors of three-dimensional objects is also described, together with its implementation results.